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1.
XU Li WU Xiaochun Lü Junchang JIA Songhai ZHANG Jiming PU Hanyong ZHANG Xingliao 《《地质学报》英文版》2014,88(4):1041-1050
Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in Luanehuan County, Henan Province. It is the second representative of lizards known from Luanchuan and adds a new member to the Luanchuan Fauna. F. luanchuanensis is a small-sized lizard and systematically assigned to the Polyglyphanodontidae of the Teiioidea because of the presence of a caniniform tooth and an elongate posterior process of the postorbital. It is distinctive in that the heterodont dentition bears 19 teeth in both the upper and lower jaws, the 3^rd maxillary tooth is large and caniniform, the post-caniniform teeth in maxilla and those posterior to the 3^rd dentary tooth are chisel-like in lateral view, the prefrontal possesses a fossa on its lateral surface, the postorbital with an extremely elongate posterior process and the well-developed retroarticular process has a deep fossa on its dorsal surface. In phylogeny, our analysis suggests a close relationship of Funiusaurus to the large-sized Tianyusaurus from the same basin within the Tuberocephalosaurinae. The discovery of Funiusaurus is significant in confirming the status of the Tuberocephalosaurinae, which includes a group of the Asian members of the Polyglyphanodontidae only. 相似文献
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The objective of this study is to determine the geochemical role of molluscs in the distribution of uranium in the marine ecosystem. Biogeochemical studies are carried out on recent mollusc shells from the Caspian Sea, Sea of Japan, Sea of Marmara, Aegean Sea, Black Sea, Mediterranean Sea, Baltic Sea, and Indian Ocean, which differ from each other in terms of physical, chemical, geographic, and geochemical characteristics. In this study, nine Gastropoda and fifty-four Pelecypoda shells of different species are analyzed to document variations of uranium in seasonal layers, which were formed by the seasonal carbonate-organic phase of molluscs during their entire lives. Shell used in this study principally comprises three layers: upper (outer) prismatic, middle prismatic, and inner (mother-of-pearl) layers. In addition, when possible, the head, the middle, and the lower parts of the shells are used for analyses separately. Also, the biological accumulation rate values for each different mollusc species rel 相似文献
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Kohei TANAKA Lü Junchang LIU Yi HUANG Zhiqing Yoshitsugu KOBAYASHI HUANG Dong Darla K. ZELENITSKY 《《地质学报》英文版》2012,86(2):294-303
The Zhutian and Dafeng formations (Upper Cretaceous) of the Heyuan Basin in northeastern Guangdong Province, China, have produced thousands of dinosaur eggs. Macromorphological features (egg diameter, egg shape, outer surface texture, and shell thickness) of 461 eggs were analyzed using non-destructive techniques and subjected to statistical analyses in order to assess their diversity and taxonomic affinities. Three types (1, 2 and 3) of eggs were discerned based on shape and outer surface morphology. Type 1 eggs are spherical to ellipsoidal in shape and have a rough surface. Three subtypes (Type 1-A-1, 1-A-2, and 1-B) are apparent from scatter plots and cluster analyses of egg diameters and shell thickness. Type 2 eggs are elongate with linear ornamentation on the surface, and are comparable to eggs that belong to the oofamily Elongatoolithidae. Type 3 eggs are elongate with a smooth surface, and are assigned to the oofamily Prismatoolithidae. Macromorphological features of the various egg types suggest that Type 1 could have been laid by ornithischian, sauropod or therizinosaur dinosaurs, Type 2 by oviraptorids, and Type 3 by troodontids. This study represents the first comprehensive statistical analysis of macrofeatures of dinosaur eggs, and reveals taxonomic diversity in the dinosaurs that were laying eggs in the Upper Cretaceous Heyuan area heretofore unrecognized in skeletal remains. 相似文献
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Joern Thiede Ola M. Johannessen 《《幕》》2008,31(1):163-167
The Nordic countries have produced famous polar explorers and researchers who have generated climate research schools at a variety of locations. The dependence of these countries with respect to the lifelihood of their societies, of their use of lands and seas, the exploitation of marine living and non-living resources have made climate research an eminent topic, and many outstanding discoveries of longand short-term climate change have been made for the first time in Scandinavia. These include early contributions to our understanding of the geological effects of continent-wide glaciations during the ice ages, the complex postglacial history of the Baltic Sea and the varved sediment sequences preserved from lakes with an extraordinary seasonality in their sediment input, as well as the detailed records of temperature, ice texture and impurities and greenhouse gas variations of the last Glacial and of the Holocene preserved in the ice cores from Greenland. Iceland with its volcanic sequences and intercalated sediment layers not only preserved the history of this subaerial segment of the mid-Atlantic Ridge, but also easily datable paleoclimate records. The fate of the Vikings, who settled during the Medieval climate optimum on Iceland and later on Greenland and who lost their habitat on Greenland at the beginning of the Little Ice Age, illustrates vividly the climate-dependent subsistence of the indigenous and non-indigenous Scandinavian populations. Modern Scandinavian climate research institutions also include sophisticated modelling groups. 相似文献
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Dinosaur eggshells from the Cretaceous red beds of southern China were selected for element geochemical study.The concentrations of the major elements indicate that the eggshells did not change much in their chemical composition after they were formed.Variations in the contents of trace elements and REEs imply that a palaeoclimatic anomaly might occur during Late Cretaceous. 相似文献
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In spite of tremendous discoveries of dinosaur eggs and nests over the world, dinosaur embryonic remains are rare. Until today, dinosaur embryos associated with eggshells are only known in about 20 cases, most of which were recovered from broken or crushed eggs. Here we report intact dinosaur eggs in a partial clutch with preserved embryonic remains in eggs from the Upper Cretaceous Nanxiong Formation of Ganzhou in the southern Jiangxi Province of China. Based on macro- and microscopic features of eggs and eggshells, these eggs were identified as Elongatoolithus sp., and possibly belong to oviraptorosaurs. A CT scanning topography revealed that all the eggs contain accumulations of embryonic bones, including possible femur and tibia. Our discovery suggests that dinosaur embryos might be preserved more than we have recognized, because intact eggs potentially confine embryonic remains. 相似文献
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Delineation of groundwater potential zones in Wadi Saida Watershed of NW-Algeria using remote sensing,geographic information system-based AHP techniques and geostatistical analysis 
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下载免费PDF全文 Sustainable management of groundwater resources has now become an obligation,especially in arid and semi-arid regions given the socio-economic importance of this resource.The optimization in zoning for groundwater exploitation helps in planning and managing groundwater supply works such as boreholes and wells in the catchment.The objective of this study is to use remote sensing and GIS-based Analytical Hierarchy Process(AHP)techniques to evaluate the groundwater potential of Wadi Saida Watershed.Spatial analysis such as geostatistics was also used to validate results and ensure more accuracy.Through the GIS tools and remote sensing technique,earth observation data were converted into thematic layers such as lineament density,geology,drainage density,slope,land use and rainfall,which were combined to delineate groundwater potential zones.Based on their respective impact on groundwater potential,the AHP approach was adopted to assign weights on multi-influencing factors.These results will enable decision-makers to optimize hydrogeological exploration in large-scale catchment areas and map areas.According to the results,the southern part of the Wadi Saida Watershed is characterized as a higher groundwater potential area,where 32%of the total surface area falls in the excellent and good class of groundwater potential.The validation process revealed a 71%agreement between the estimated and actual yield of the existing boreholes in the study area. 相似文献
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LiuJiangping XiaJianghai ChenChao ZhangSuxin 《中国地质大学学报(英文版)》2003,14(4):363-367
The application of the seismic reflection method is often limited in complex terrain areas.The problem is the incorrect correction of time-shift caused by topography. To apply normal moveout(NMO) correction to reflection data correctly, static corrections are necessary to be applied in advance for the compensation of the time distortions of topography and the time-delays from near-surface weathered layers. For environment and engineering investigation, weathered layers are our targets so that the static correction mainly serves the adjustment of time-shift due to an undulating surface. In practice,seismic reflected raypaths are assumed to be almost vertical through the near-surface layers because they have much lower velocities than layers below. This assumption is typically acceptable in most cases since it results in little residual error for small elevation changes and small offsets in reflection events. Although static algorithms based on choosing a floating datum related to common midpoint gathers or residual surface-consistent functions are available and effective, errors caused by the assumption of vertical raypaths often generate pseudo indications of structures. This paper presents the comparison of applying corrections based on the vertical raypaths and bias (non-vertical) raypaths. It also provides an approach of combining elevation and NMO corrections. The advantages of the approach are demonstrated by a synthetic example of multi-coverage seismic reflection surveys on rough topography. 相似文献
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The paper deals with the relatively weak permeable layer in a layered structure of a slope rock mass and itseffect on groundwater behaviour in the rock mass. When the whole groundwater table is declined in such typeof slope rock mass, the permeability of the relatively weak permeable layer in the middle will be several timeslower than that of the upper and lower permeable layers and consequently the water level in layers of differentpermeability will fall in different rates which will lead to a discontinuous phenomenon of the water body. Amethod of finite element simulation on a vertical two-dimensional profile is suggested for the study of the phe-nomenon and its application to practical situation is described. The calculation result shows that the existingweak permeable layer in a layered slope rock mass exerts unnegligible influence on the variation of water levelin the rock mass of a slope. The result also proves the applicability of the finite element simulation method. 相似文献
10.
JIA Bingwen ZHOU Anchao MA Mailing JIA Xiaoyun Department of Earth Sciences Taiyuan University of Technology Taiyuan Shanxi 《《地质学报》英文版》2001,75(2):184-195
Upper Carboniferous-Lower Permian volcanic event deposits from two cross sections in Nanpiao, Liaoning Province, and the Daqing Mountains, Inner Mongolia, were examined by systematic rock and mineral identification, differential thermal analysis, X-ray diffraction, scanning electron microscopy and trace element and rare earth element quantitative analysis. According to the results, twelve sequences of volcanic event deposits have been distinguished from bottom to top, including 34-39 volcanic event layers. As these layers each have their own distinctive petrological, mineralogical and geochemical characteristics and were derived from the same source, they provide new evidence for further ascertaining the distribution characteristics of volcanic event deposits on the northern margin of the North China plate and carrying out the stratigraphic correlation using volcanic event layers as marker beds. 相似文献
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Early Cretaceous spheroolithid eggshells have always been extremely scarce, unlike their putative egg layers, ornithopod dinosaurs, which are ubiquitous in Early Cretaceous ecosystems. In this paper, we re-evaluate eggshells previously assigned to the oofamily Elongatoolithidae, an oofamily related to derived theropod dinosaurs (including maniraptorans and oviraptorids), and reassign them to the oofamily Spheroolithidae, on the basis of the lack of a squamatic ultrastructure, and the presence of a prolatocanaliculate pore system and undulating extinction, typical of spheroolithid eggshells. We erect a new oogenus, Guegoolithus to include material previously reported as Macroolithus turolensis Amo-Sanjuan, Canudo and Cuenca-Bescós 2000, and new material from several lower Barremian localities of the Maestrazgo Basin in Spain. Guegoolithus eggshells exhibit an acicular radial ultrastructure in the lower part of the shell units, which develops into a tabular radial ultrastructure in the upper part, giving an appearance of a two-layered eggshell in thin sections that is not seen in SEM pictures. These features fill the gap between the two-layered prismatic eggshell of ceratopsians and the prolatospherulitic ornithopod eggshell of derived hadrosaurs. 相似文献
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汝阳盆地是豫西地区的一个中—新生代断陷盆地,自2006年以来发现了一个以巨型蜥脚类恐龙为代表的恐龙动物群。本文描述了近期发现于汝阳盆地下白垩统郝岭组中的若干恐龙蛋蛋壳碎片。基于以下对蛋壳宏观形态和显微特征的分析,这些蛋壳碎片可以归入长形蛋科(Elongatoolithidae)的长形蛋属(Elongatoolithus):蛋壳外表面具分散瘤点状或线性脊状的纹饰;蛋壳自内而外分为锥体层和柱状层,二层之间的界线不清晰;锥体层中锥体排列紧密;柱状层中具波浪状的平行生长纹。这一发现代表了长形蛋属在早白垩世地层中的首次记录,进一步拓展了该蛋属的地史和古地理分布。由以往已知的化石关联推测,这些蛋壳可能与该层位中的窃蛋龙类如刘店洛阳龙(Luoyanggia liudianensis)等具有相关性,表明汝阳盆地在早白垩世晚期具有适宜该类恐龙生存与繁殖的环境。 相似文献
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The fossil record of small-sized theropods in south-western Europe is scarce and fragmentary. In absence of more direct evidence, the oological record arises as an alternative source of information to infer biodiversity. In this regard, the controversial dinosaur eggshells from the Les Labadous locality in southern France are herein re-evaluated in the light of new material and current parataxonomic information. New data and analyses reveal a new eggshell type, Montanoolithus labadousensis oosp. nov., characterized by a unique combination of characters. Additionally, the phylogenetic analysis reinforces the placement of the new oospecies as the sister taxon of the North American Montanoolithus strongorum, refusing the previous attribution of the Les Labadous remains to Elongatoolithidae. The combination of microstructural and phylogenetic results suggests that Montanoolithus labadousensis was likely produced by a dromaeosaurine dromaeosaurid, a taxonomic attribution that is consistent with the biodiversity of small-sized theropods at the latest Cretaceous of south-western Europe. 相似文献
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《China Geology》2018,1(1):28-35
An alvarezsaurid dinosaur skeleton was discovered from the Late Cretaceous Qiupa Formation of Luanchuan, Henan Province of central China. It represents a new alvarezsaurid dinosaur Qiupanykus zhangi gen. et sp. nov. A phylogenetic analysis recovers Qiupanykus nested within the unresolved clade, which includes Asian and north American taxa. The skeleton of the new specimen is preserved in association with eggshells. The eggshell morphologies show that these eggs belong to oviraptorid eggs, skeletal remains of which were discovered from the same area. The alvarezsaurid skeleton associated with eggshell fragments may indicate that these eggs were broken by the strong thumb-claws of the former and that alvarezsaurid dinosaurs may be egg-eaters. 相似文献
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栾川石煤是河南省境内一种比较特殊的煤种,主要分布于栾川群煤窑沟组上段,一般含石煤层2层,个别地段为3层或4层。可采石煤为第一层,厚度1．40～13．10m,一般为4-6m,分布面积大,层位稳定,连续性较好;原煤发热量4．08~12．41MJ／kg,平均7．26MJ／kg,灰分产率58．08％～82．09％,全硫平均含量1．72％,为中硫、高灰分、低发热量的劣质煤。栾川含石煤地层及煤层的分布与黄背岭一石宝沟背斜关系密切,呈环带状分布于背斜四周,变辉长岩与石煤的出露形影相依,为找矿标志层。 相似文献
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浙江天台盆地蛋化石与恐龙的绝灭 总被引：9，自引：1，他引：9
综合报道了浙江天台盆地产出的蛋化石，其中包括新建立的龟鳖化石蛋科(新科)Tesmdoolithidae ram. nov.和天台蛋属(新属)Tiantaioolithus gen. nov.,以及5个新种：Dendroolithus shuangtangensis sp. nov.,Elongatoolithus chichengshanensis sp. nov,Elongatoolithus laijiaensis sp. nov,Spheroolithus jincunensis sp. nov,Tiantaioolithus jiangi sp. nov。这批蛋化石以赤城山组出现的类型最为丰富，有长形蛋、树枝蛋、圆形蛋、龟鳖类化石蛋等；赖家组蛋化石数量少，仅见长形蛋和圆形蛋类，其时代均为晚白垩世。推测天台蛋化石消失的原因是由于气候变冷，受精卵不能正常孵化所致。孵化率降低，生殖链打断，可能是引起恐龙绝灭的原因之一。 相似文献
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河南栾川地区陈南沟钼矿区土壤地球化学异常的
特征与评价 总被引：2，自引：0，他引：2
陈南沟钼矿区位于东秦岭钼矿带栾川矿集区内,地处栾川断裂南侧,属北秦岭褶皱系。将矿区成矿地质环境与土壤地球化学特征结合,利用地质累积指数对研究区内的土壤地球化学元素组合进行评价,综合分析后圈出找矿有利靶区,并对靶区进行了野外检查和工程验证。研究结果表明：陈南沟钼矿属于与老君山花岗岩体有关的热液矿床,燕山期红岩寨花岗岩体边部及其外接触带是钼矿化富集的有利部位,北东向小型构造对辉钼矿的形成起到一定的控制作用。本次工作完善了与花岗岩基有关的热液矿床研究,对栾川矿集区内进一步的找矿工作具有一定的指导意义。 相似文献